WASHINGTON (CNN) -- The dramatic drop in violence in Iraq is due in large part to a secret program the U.S. military has used to kill terrorists, according to a new book by Pulitzer Prize-winning journalist Bob Woodward.

The program -- which Woodward compares to the World War II era Manhattan Project that developed the atomic bomb -- must remain secret for now or it would "get people killed," Woodward said Monday on CNN's Larry King Live.

"It is a wonderful example of American ingenuity solving a problem in war, as we often have," Woodward said.

In "The War Within: Secret White House History 2006-2008," Woodward disclosed the existence of secret operational capabilities developed by the military to locate, target and kill leaders of al Qaeda in Iraq and other insurgent leaders.

"If you were a member of al Qaeda or the resistance or some extremist militia, you would be wise to get your rear end out of town," Woodward said. "It is very dangerous."

Maher jokes about 'exploding baskets' and Woodward says 'you're not far off'. But you have to think this is something to do with technology? Analysing communications, locating and targeting, something like that ...